Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
  • H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
  • H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L25/00—Baseband systems
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
  • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
  • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
  • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
  • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
  • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
  • H04B7/0636—Feedback format
  • H04B7/0639—Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
  • H04L1/0056—Systems characterized by the type of code used
  • H04L1/007—Unequal error protection
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
  • H04L1/0072—Error control for data other than payload data, e.g. control data
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/02—Arrangements for detecting or preventing errors in the information received by diversity reception
  • H04L1/06—Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L25/00—Baseband systems
  • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
  • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
  • H04L25/03891—Spatial equalizers
  • H04L25/03898—Spatial equalizers codebook-based design
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L25/00—Baseband systems
  • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
  • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
  • H04L25/03891—Spatial equalizers
  • H04L25/03949—Spatial equalizers equalizer selection or adaptation based on feedback
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
  • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
  • H04L1/0026—Transmission of channel quality indication
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
  • H04L1/0056—Systems characterized by the type of code used
  • H04L1/0071—Use of interleaving
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/0001—Arrangements for dividing the transmission path
  • H04L5/0003—Two-dimensional division
  • H04L5/0005—Time-frequency
  • H04L5/0007—Time-frequency the frequencies being orthogonal, e.g. OFDM(A), DMT
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/003—Arrangements for allocating sub-channels of the transmission path
  • H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W28/00—Network traffic management; Network resource management
  • H04W28/02—Traffic management, e.g. flow control or congestion control
  • H04W28/04—Error control

Definitions

• the present invention relates to the field of communications technologies, and in particular, to a method and apparatus for transmitting and receiving precoding information.
• the data sender (such as
• NodeB Node B
• BS Base station, etc.
• the terminal such as UE (User Equipment), MS (Mobile Station), etc.) (such as PMI (Precoding Matrix) Indicator, precoding matrix indication) and the locally pre-stored codebook, pre-process the data to be sent and then send it to the terminal, so that the data transmission process can adapt to the change of the channel state, thereby improving the performance of the data transmission. Therefore, how to send It is important to receive the above precoding information.
• the terminal such as UE (User Equipment), MS (Mobile Station), etc.
• PMI Precoding Matrix Indicator, precoding matrix indication
• the locally pre-stored codebook pre-process the data to be sent and then send it to the terminal, so that the data transmission process can adapt to the change of the channel state, thereby improving the performance of the data transmission. Therefore, how to send It is important to receive the above precoding information.
• the system uses a single codebook whose precoding matrix is indexed by a single PMI (precoding matrix indicator), which can pass PUCCH (Physical Uplink Control Channel, physics).
• PMI Physical Uplink Control Channel
• the uplink control channel and the PUSCH Physical Uplink Shared Channel perform periodic and aperiodic reporting.
• the wideband precoding matrix indicates that the PMI is prone to error propagation. Therefore, it is necessary to further study the reporting mode to improve system performance.
• Embodiments of the present invention provide a method and apparatus for transmitting and receiving precoding information to improve system performance.
• an embodiment of the present invention provides a method for transmitting precoding information, where the method Includes:
• the terminal acquires a broadband precoding indication PMI;
• the terminal separately encodes the MSB of the broadband PMI or jointly encodes the MSB of the broadband PMI and other information of the N bits to obtain the encoded information, where the MSB is part of the broadband PMI, and N is a natural number;
• the terminal sends the encoded information to the data sending end.
• an embodiment of the present invention provides a method for receiving precoding information, where the method includes:
• the data sending end receives the encoded information sent by the terminal
• the encoded information is: information obtained by separately encoding the MSB of the broadband PMI or jointly coding the MSB of the broadband PMI and other information of N bits after the terminal acquires the wideband precoding indication PMI, where the MSB For a portion of the wideband PMI, N is a natural number.
• an embodiment of the present invention provides a device for transmitting precoding information, including: an information acquiring unit, configured to acquire a broadband precoding indication PMI;
• An information encoding unit configured to separately encode the MSB of the broadband PMI or jointly encode the MSB of the broadband PMI and other information of the N bits to obtain encoded information, where the MSB is part of the broadband PMI, where N is Natural number;
• an information sending unit configured to send, by the data sending end, the information encoded by the information encoding unit.
• an embodiment of the present invention provides a precoding information receiving apparatus, including: an information receiving unit, configured to receive encoded information sent by a terminal;
• the encoded information is: information obtained by separately encoding the MSB of the broadband PMI or jointly coding the MSB of the broadband PMI and other information of N bits after the terminal acquires the wideband precoding indication PMI, where the MSB For a portion of the wideband PMI, N is a natural number.
• the embodiment provided by the embodiment of the present invention improves the broadband precoding information by separately encoding the MSB in the wideband PMI and transmitting or jointly coding and transmitting with the N bits of other information. Reliability, reduced error propagation, further improving precoding performance.
• FIG. 1 is a schematic flow chart of a method for transmitting and receiving precoding information according to an embodiment of the present invention
• FIG. 2 is a schematic diagram of resource mapping of encoded information on a PUSCH according to an embodiment of the present invention
• FIG. 3 is a schematic diagram of another resource mapping of the encoded information on the PUSCH according to the embodiment of the present invention.
• FIG. 4 is a schematic flowchart of another method for transmitting and receiving precoding information according to an embodiment of the present invention.
• FIG. 5 is a schematic structural diagram of a device for transmitting precoding information according to an embodiment of the present invention
• FIG. 6 is a schematic structural diagram of a device for receiving precoding information according to an embodiment of the present invention.
• an embodiment of the present invention provides a method for transmitting precoding information, where the system bandwidth is divided into at least one subband, and the method includes:
• the terminal acquires a broadband PMI
• the terminal may obtain the broadband PMI according to the preset criteria, and may also obtain the broadband PMI according to other methods in the prior art. For example, the terminal obtains the broadband PMI according to the preset criteria, and the terminal may be based on the preset criterion. Calculating the wideband precoding matrix indicating PMI, as shown in equation (1):
• ⁇ denotes a codeword in single codebook C
• ( ⁇ ) denotes a corresponding criterion 1 System bandwidth and the objective function of the precoding matrix ⁇ .
• the foregoing preset criterion 1 may be a throughput maximization criterion
• the target function corresponding to the criterion may be a throughput maximization function, which may be implemented based on information capacity calculation, or may be based on Mutual information or mutual information deformation (such as the weight of mutual information) and so on.
• the preset criterion 1 is an example of the capacity maximization criterion, which is similar to the above, and will not be described here.
• the objective function corresponding to the preset criterion can be flexibly set according to the actual application status, and this is not specifically limited.
• the terminal calculates the broadband precoding matrix indication PMI based on the preset criterion 2, as shown in the formula (2) (3):
• f 2 (W j ) ⁇ max f s ⁇ g (W i , W f )) (3)
• the matrices ⁇ , and ⁇ 2 pass through the person ⁇ respectively.
• ⁇ , 2 is obtained from two codebook CI and C2 indices, which are respectively used to indicate the broadband characteristics and frequency selectivity characteristics of the channel.
• / 2 ( ⁇ ) represents the system function of the system bandwidth and the wideband precoding matrix ⁇ corresponding to the preset criterion 2.
• the objective function representing the subband and precoding matrix ⁇ corresponding to the preset criterion 2 ⁇ is the total number of subbands constituting the system bandwidth.
• it is said to be a wideband precoding matrix indicating broadband.
• the foregoing preset criterion 2 may be a throughput maximization criterion
• the target function corresponding to the criterion may be a throughput maximization function, which may be implemented based on information capacity calculation, or may be based on Mutual information or mutual information deformation (such as the weight of mutual information) and so on.
• the objective function corresponding to the preset criterion can be flexibly set according to the actual application state, and this is not specifically limited.
• the method may further include:
• the terminal separately codes the MSB (Most Significant bits) of the broadband port; Wherein, the MSB may be part of the broadband PMI.
• the MSB (Max Significant Bits, the highest bit) of the broadband PMI obtained in step 101 is ".,”! , , ... ⁇ —! Indicates, where A is the number of MSB bits of the wideband PMI.
• the terminal encodes the MSB of the wideband PMI obtained in step 101 with a (20, A) code (refer to 3GPP LTE TS 36.212 V9.0.0), where the codeword of the (20, A) code is linear of 13 base sequences.
• the code can be used according to the actual application.
• the method is flexible and is not specifically limited.
• the MSB of the broadband PMI may be part of the broadband PMI, or may be all bits of the broadband PMI.
• the MSBs that are only part of the wideband PMI are separately encoded and transmitted, saving overhead compared to separately encoding and transmitting the entire wideband PMI.
• the MSB is the main component information of the PMI. Even if the component information of the remaining PMI other than the MSB, such as the LSB (Least Significant Bits), is not correctly transmitted, the impact on the system performance is small.
• the terminal sends the encoded information to a data sending end.
• the terminal may send the encoded information to the data sending end by using a physical uplink control channel PUCCH. Further, when the encoded information is transmitted through the PUCCH, the same period as the rank indication (RI) can be employed.
• PUCCH physical uplink control channel
• the terminal may send the encoded information to the data transmitting end through the physical uplink shared channel PUSCH.
• the encoded information may be mapped to a PUSCH solution by a channel interleaver
• a channel interleaver On both sides of the pilot signal or reference signal (Reference Signal, RS), as shown in FIG. 2 or FIG. 3, SO to S13 represent SC-FDMA symbols in one subframe, and the position shown in the MSB box is encoded information.
• the encoded information can be mapped to all layers for transmission.
• MIMO Multiple Input Multiple Output
• the data sending end receives the encoded information sent by the terminal.
• the data sending end may receive the encoded information sent by the terminal through the physical uplink control channel PUCCH.
• the data sending end may receive the encoded information sent by the terminal through the physical uplink shared channel PUSCH.
• the encoded information may be mapped to two adjacent to the demodulation pilot or the reference signal by using a channel interleaver.
• the side is received as shown in the MSB in Figure 2 or 3.
• the precoding indicates that there is a mapping relationship between the PMI and the precoding matrix, where the mapping relationship is such that the distance between the precoding matrices corresponding to the two PMIs different from the highest MSB is greater than the difference between the least significant LSBs.
• the distance between the precoding matrices corresponding to the PMI which can be defined as the chord distance:
• £ represents the chord of two matrices A and B, where matrix A is the same as B, A H represents the conjugate transpose of matrix A, and
• ⁇ represents the Frobenius norm.
• the definition of the distance can be flexibly defined according to the actual application situation, and this is not specifically limited.
• the MSB of the above broadband PMI may include a part of the broadband PMI or all the broadband PMIs.
• the data sending end may also obtain the broadband or frequency selective precoding information obtained by other feedback methods.
• a broadband or frequency selective precoding matrix may also obtain the broadband or frequency selective precoding information obtained by other feedback methods.
• the method for transmitting and receiving precoding information improves the reliability of the wideband precoding information and reduces the error propagation by separately encoding and transmitting the MSB in the wideband PMI, thereby further improving the precoding. performance.
• an embodiment of the present invention provides a method for transmitting precoding information, where the system bandwidth is divided into at least one subband, and the method includes:
• the terminal acquires a broadband PMI
• the terminal may obtain the broadband PMI according to the preset criteria, and may also obtain the broadband PMI according to other methods in the prior art.
• the terminal obtains the broadband PMI according to the preset criteria, and the terminal may be based on the preset criterion. Calculating the wideband precoding matrix indicating PMI, as shown in equation (1).
• the objective function corresponding to the preset criterion can be flexibly set according to the actual application state, and this is not specifically limited.
• the terminal calculates the broadband precoding matrix indication PMI based on the preset criterion 2, as shown in the formula (2) (3).
• the target function corresponding to the preset criterion can be flexibly set according to the actual application state, and this is not specifically limited.
• the method may further include:
• the terminal jointly encodes the MSB of the broadband PMI with other information of the N bits; wherein the MSB is part of the broadband PMI.
• the MSB (Max Significant Bits) of the wideband PMI obtained in step 201 is represented by A bits, and the other information of the N bits may be other bits than the MSB of the wideband PMI, such as a rank indication RI. , or may be a hybrid automatic repeat request (ACK/NACK) information of the HARQ request.
• the terminal combines the MSB of the wideband PMI with the other information of the N bits into a bit sequence of length A+N.
• the terminal encodes the bit sequence of length A+N by a (20, A+N) code, and the code can adopt a code similar to the embodiment shown in FIG.
• the MSB of the broadband PMI may be part of the broadband PMI, or may be all bits of the broadband PMI.
• the terminal sends the encoded information to a data sending end.
• the terminal may send the encoded information to the data sending end by using a physical uplink control channel PUCCH. Further, when the encoded information is transmitted through the PUCCH, the same period as the rank indication (RI) can be employed.
• PUCCH physical uplink control channel
• the terminal may send the encoded information to the data transmitting end through the physical uplink shared channel PUSCH.
• the encoded information may be mapped to the two sides of the PUSCH demodulation pilot or reference signal (Reference Signal, RS) through a channel interleaver, as shown in FIG. 2 or FIG. 3, and SO to S13 represent one sub- The SC-FDMA symbol in the frame, the position indicated by the MSB box is the position to which the encoded information is mapped, and the RS box in the figure shows the position to which the RS is mapped.
• Reference Signal Reference Signal
• the encoded information can be mapped to all layers for transmission.
• MIMO Multiple Input Multiple Output
• the data sending end receives the encoded information sent by the terminal.
• the data sending end may receive the encoded information sent by the terminal through the physical uplink control channel PUCCH.
• the data sending end may receive the encoded information sent by the terminal through the physical uplink shared channel PUSCH.
• the encoded information may be mapped to two adjacent to the demodulation pilot or the reference signal by using a channel interleaver.
• the side is received as shown in the MSB in Figure 2 or Figure 3.
• the precoding indicates that there is a mapping relationship between the PMI and the precoding matrix.
• the mapping relationship is such that the distance between the precoding matrices corresponding to the two PMIs different in the highest bit MSB is greater than the distance between the precoding matrices corresponding to the two PMIs different in the lowest bit LSB, and the distance may be defined as a chord distance, specifically As shown in formula (5).
• the definition of the distance can be flexibly defined according to the actual application situation, and this is not specifically limited.
• the MSB of the above broadband PMI may include a part of the broadband PMI or all the broadband PMIs.
• the data transmitting end can also obtain a reliable wideband or frequency selective precoding matrix together with the broadband or frequency selective precoding information obtained by other feedback methods.
• the method for transmitting and receiving precoding information jointly encodes and transmits MSB and N bits of other information in the wideband PMI, thereby improving the reliability of the wideband precoding information and reducing error propagation.
• the precoding performance is further improved.
• an embodiment of the present invention provides a device for transmitting precoding information, which is applicable to a system in which a bandwidth is divided into at least one subband, and the device includes:
• An information obtaining unit 301 configured to acquire a broadband precoding indication PMI
• the terminal may obtain the broadband PMI according to the preset criteria, and may also obtain the broadband PMI according to other methods in the prior art.
• the terminal obtains the broadband PMI according to the preset criterion, and the information acquiring unit is based on the preset.
• the criterion 1 calculates the wideband precoding matrix indicating PMI, as shown in equation (1).
• the information acquiring unit calculates the broadband precoding matrix indication PMI based on the preset criterion 2, as shown in the formula (2) (3).
• the information encoding unit 302 is configured to separately encode the MSB of the broadband PMI or jointly encode the MSB of the broadband PMI and other information of the N bits to obtain encoded information, where the MSB is part of the broadband PMI, N Natural number;
• the information sending unit 303 is configured to send the information encoded by the information encoding unit to the data transmitting end.
• the device for transmitting precoding information in the embodiment of the present invention may specifically be a terminal.
• the apparatus for transmitting precoding information improves the reliability of the broadband precoding information by separately encoding and transmitting the MSB in the wideband PMI or jointly coding with the N bits of other information.
• the error propagation is reduced, which further improves the precoding performance.
• an embodiment of the present invention provides a device for receiving precoding information, which is applicable to a system in which a bandwidth is divided into at least one subband, and the device includes:
• the information receiving unit 601 is configured to receive the encoded information sent by the terminal.
• the encoded information is: information obtained by separately encoding the MSB of the broadband PMI or jointly coding the MSB of the broadband PMI and other information of N bits after the terminal acquires the wideband precoding indication PMI, where the MSB For a portion of the wideband PMI, N is a natural number.
• the apparatus for receiving precoding information improves the broadband pre-processing by receiving information that is separately encoded by the MSB in the broadband PMI and information that is jointly encoded and transmitted with N bits of other information.
• the reliability of the encoded information reduces error propagation, thereby further improving the precoding performance.
• the data transmitting end in the foregoing embodiment may be a NodeB (Node B), a BS (Base station), a home base station, or a relay station.
• the terminal may be a UE (User Equipment), MS (Mobile). Station, mobile station).
• All or part of the technical solutions provided by the above embodiments may be implemented by software programming, and the software programs thereof are stored in a readable storage medium such as a hard disk, an optical disk or a floppy disk in a computer.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Physics & Mathematics (AREA)
• Mathematical Physics (AREA)
• Power Engineering (AREA)
• Mobile Radio Communication Systems (AREA)
• Radio Transmission System (AREA)
• Reduction Or Emphasis Of Bandwidth Of Signals (AREA)
• Compression, Expansion, Code Conversion, And Decoders (AREA)
• Detection And Prevention Of Errors In Transmission (AREA)

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